When the short grain matures early and you don't know whether to harvest, who you gonna call?

The extension office, of course. But at a new telephone number. Starting Monday, the Maryland Cooperative Extension service office phone number will be 410-386-2760, or toll free at 888-326-9645.

If you lose the number -- and the kitchen magnet the office is sending to 5,000 newsletter subscribers -- the phone book will be no help. It will have the old number.

Since at least the Eisenhower administration, Carroll County farmers knew that if they couldn't depend on cooperative weather, they could count on reaching the cooperative extension agent at 4611.

Lately, the full number has been 410-848-4611. Aside from the area code, it has remained unchanged since 1962.

Before that, when phone numbers had names instead of numerical prefixes, it was Tilden 8-4611, said Robert L. Jones, retired extension director. That was the number when he became an associate director in 1957. For all anyone knows, "4611" is the only phone number the 81-year-old institution has had.

"This will be confusing, won't it?" Jones said as he took down the new number.

For many farmers and 4-H leaders, the extension service phone number is one they rattle off as if it were their home number.

"If I need anything, I'll just dial the old number and a recording will give me the new one," said Blaine Harman, a Taneytown dairy farmer.

He won't be alone, but that might work only for a month or so, warned Extension Office Director David L. Greene. He will try to extend the transition, he said, but isn't sure that he can.

"We get a lot of seasonal calls," Greene said. Gardeners might not call again until spring. Debt-ridden families might not need to call the office financial-management experts until credit cards start bearing the weight of Christmas purchases.

The change is for the sake of technology. The extension office is part of county government, which is switching all departments to one large GTE Corp. phone system that will be able to transfer not just voice phone calls, but video and data from computers as well. That means departments can have video- and teleconferences and send electronic-mail messages, Greene said.

Why not keep the old number for people who need a friendly and familiar voice on the other end?

Harman calls the office four or five times a year, he said. When the short grain (wheat and barley) matured a few weeks earlier than usual this spring, he called for advice on whether to harvest early or wait for more yield. The agents recommended harvesting, so he did.

Even though the old number has long been entered into the speed-dialer on Dan and Eleanor Shipley's phone -- the longtime farmers need only dial "Memory 05" -- Eleanor Shipley knows the number by heart.

"I have to ask my grandson to change that on our phone," she said.

Her husband called the extension service yesterday morning for help getting rid of pesky groundhogs that are disturbing the small family cemetery on their property.

She calls more often in her volunteer activities with Family Community Education and 4-H.

Linwood dairy farmer Gary Bowerman called, too. He needed to find an animal renderer to remove 10 cows that had been struck by lightning the day before. With the loss in income that will result from losing some of his best-producing cows, it is likely Bowerman could call the extension office again soon.

The calls are enough to keep five secretaries busy answering phones. Often, three are on the phone at once.